Process of concentrating nitric acid.



"Bnuno THOMAS, or sEATTL E', WASHINGTON.

PROCESS OF CONQENTRATING NITRIC ACID. H

No Drawing;

To all whom it may concern:

Be it known that I, BRUNO THOMAS, a

' citizenof the United States, and resident of lower nitrogen oxide,

. jectionable.

the city of Seattle, county of King, and State of Washington, haveinvented certain new and useful Improvements iir Processes ofConcentrating Nitric Acid, ot-which the following is a specification; I;My invention relates to the manufacture of nitric acid and consists of aprocess wherein absorption of the gases is increased by the use ofpressure and concentrationand purification is increased by the use o' felectrolys'isi f j accordance with the laws of Henry and .Dolton, it hasbeen shown that the absorpa fluid is increased with the' .rpreSsureo-fthe gas uponthe fluid. I, theretionf ofgas by fore, subject gases whichcontain nitrogen to pressure {while in contact with water,

A common's ou-rce of the nitrogenous gases The product of such nitricacid which also as NO and N0 the presence ofwhich in the final productis ob- By the use of pressure during the absorption process I mayobtaina product having a concentration of 40% of nitric acid. This isimpure in that it has considerable NO and N0 1 then electrolize theliquid, that is, pass a current of electricity through it. ThisSpecification of Letters Iatent'.

Application filed July 24, 1917. Serial No. 182,898.

Patented Nov. 5, 1918.

liberates oxygen at the anode and this oxygen unites with the loweroxide of nitrogen to form nitric acid, HNO

At the same time, or alternately, as may be "desired, additional gasunder. pressure is applied, which is absorbed and then purified by theelectrolysis. In the electrolytic. action the temperature of the acidshould be kept below l0 O. The electrolytic cells used may be of thesort which treat-different charges successively, or of a continuouscharacter in which there is a flow of the-acid between the electrodes.

This process may be carried out as two consecutlve and alternatingsteps, one being jheabsorption of gas under pressure other itspurification by electrolysis, or the two steps may be overlapping andacting at the same time. The process is continued un-' til the requiredstrength of acid is obtained What I claim is:

v1. The process for the manufacture of nitri'o acid which consists inabsorption of gas by liquid under an excess pressure. and itspurification by electrolysis.

2.The process for the manufacture of nitric acid which cons sts inabsorbing ni-' trogenous gas 1n a liquld under pressure and fat-the sametime converting the lower oxids of nitrogen Signed at Seattle,-Washington, this 19th day of July 1917.

BRUNO THOMAsr-l and the into nitric acid by electrolysis;

